Horizontal transmission and expression of Epichloë typhina in orchardgrass (Dactylis glomerata)

Abstract Choke disease, which is caused by Epichloë typhina , was first reported in orchardgrass seed production fields the Willamette Valley, Oregon 1997 and has continued to persist system. The disease can cause up 30% losses yield. Unlike many species that are transmitted, it unclear how infection of E. occurs field, or spreads within plants. In this study, overall incidence choke on trap plants placed a choke-infested field 41% 2018 9% 2019. Similar occurred when exposed before (39%) after (43%) swathing 2018. Contrary our hypothesis, sprayed with an artificial honeydew had significantly lower (32%) compared controls (48%). An examination spread tillering revealed development infected tillers greater than uninfected tillers, could contribute gradual increase over time. These studies better understanding fields, important step towards developing control methods reduce fields.